Adding more thermal paste will harm your temps, not help them. How are you monitoring them? You should be using either Real Temp or Core Temp. And 65C is a perfectly fine temperature for your chip, so you don't have to worry about anything. It does seem a little bit higher than normal, but you're still well within safe levels, and there's no risk of harming your CPU.

65 is 100% safe. Adding more thermal paste is BAD. You just want enough to cover the chip (a pea/rice sized drop) so you get the most cooler-IHS contact. Thermal paste is meant for filling the microscopic impurities in the heatspreader and CPU cooler base. And again, 65C is perfectly fine. As long as you keep it under 85-90C you will be 100% fine, and even then you're just being cautious.